JLavs Notes

The Address Resolution Protocol

The Ethernet Protocol

The OSI model and the TCP/IP model

Operates on the Transport Layer of the OSI model Reliable, full featured transport layer protocol Divides data into segments TCP Header…

The Dynamic Host Configuration Protocol

Fully managed, highly available with replication across 3 AZs NoSQL database Scales to massive workloads Millions of requests per second…

To get managed Redis/Memcached In-memory databses with really high-performance, low latency Using elasticache involves heavy application…

AWS EC2, EBS & EFS EC2 User data Possible to bootstrap instances using a User Data script Only run once Used to automate tasks such as…

Vertical Scalability scaling size of instance Horitontal Scalability increasing no. of instances High Availablity Running application in…

ECS Clusters logical groupings of EC2 instances instances run the ECS agent ECS agents register the instance to the cluster EC2 instances…

AWS KMS Easy way to control access to data - AWS manages keys Fully integrated with IAM Seamlessly integrated into EBS, S3, Redshift, RDS…

Allows storage of objects (files) into buckets Must have globally unique name Naming convention No uppercase No underscores 3-63 characters…

Framework for developing and deploying serverless applications All the config is YAML code Generate complex CloudFormation from simple YAML…

Used to decouple applications Unlimited throughput Default retention, unlimited no. of messages in queue Low latency (< 10ms on publish…

Model your workflows as state machines (one per workflow) Order fulfillment, data processing Web applications, any workflow Written in JSON…

Private network to deploy your resources Subnets allow you to partition your network inside your VPC Public subnets are accessible from the…

Event producer that sends messages to one SNS topic Event recievers listen to the SNS topic and will get all the messages Up to 10,000,00…

Identity-based policies Attach managed and inline policies to IAM identities (users, groups to which users belong, or rules). Grant…

Makes it easy to collect, process and analyse streaming data in real-time Kinesis Data Streams: Capture, process and store data streams…

Visual analysis of our applications Troubleshooting performance bottlenecks Understand dependancies in a microservice architecture Pinpoint…

Root account created by default - shouldn’t be shared Users are prple within organisation and can be grouped Groups only contain users not…

Non writeable properties

A closure is a function which contains its own lexical environment. It gives you access to the outer functions scope from an inner function…

Arrays are converted to strings and then concatenated. As there are no elements in either of these arrays the concatenation is which is…

Types Tuple Null and undefined types and are subtypes of all other types, so can be assigned to or only when the flag is not used if…

Nothing exciting here really...